Comment 4 for bug 662931

I hit the same problem with this. Again, I only set up a small number of machines (I do a single lesson in using Linux once a year) but wanted an unattended setup for the 18 machines.

Currently, I'm working around this problem by creating a preseed file (based on the ubuntu.seed in the 'preseed' directory on the alternate CD) that contains the following line:

d-i mirror/country string manual

I've also set the mirror host and directory with 'mirror/http/hostname' and 'mirror/http/directory' in this file.

After setting the mirror's country to 'manual', it appears that you can then set your own mirror url.

Hope this helps.

Graham